This replacement gauge for the high pressure side has left hand threads. This means that the “righty tighty, lefty loosey” rule does not apply. To tighten this gauge, turn to the left; to loosen this gauge, turn to the right. Most regulators (about 80%) are set up with this style of threading on the high pressure side. If your regulator does not have left hand threading, this gauge will not attach.

California Proposition 65

Proposition 65 Warning: This product contains chemicals known to the State of California to cause cancer and/or birth defects or other reproductive harm.